The present invention relates to a seal for use with a stroking universal joint bellows.
More specifically, the present invention relates to a novel seal adaptor for use on a housing in a tripot type universal joint.
Stroking universal joints for use in connection with constant velocity joints are well known in the art. One such type of stroking joint is a tripot type. Very generally, a tripot type universal joint includes a housing that is configured to reduce weight by use of a non-round outer surface (non-circular outer profile). The normal method of attaching the round end of a thermoplastic seal to a tripot joint (or other non-round) housing is to use a seal adaptor made from a pliable thermoplastic rubber or thermoset rubber. The prior art seal adaptor has a non-round inner surface which is configured to conform to the shape of the non-round outer surface of the housing. The seal adaptor further is configured with a round outer surface which will conform to the inside diameter of a boot seal. When a clamp is installed over the end of the boot seal and tightened, it is desirable for the seal adaptor to deform in response to the clamping force so as to provide a uniform compression force and provide a good seal between the housing and adaptor as well as a good seal between the adaptor and the boot seal.
Such tripot type bellows seal joints ideally should have a uniform clamping force between the seal adaptor and the boot seal and also between the seal adaptor and the non-uniform surface of the joint housing. In fact, because of the complex shape of the adaptor, it has been found that sealing/clamping forces can vary considerably around the sealing surfaces due to an unequal distribution of stiffness of the seal adaptor attributable to the variations in cross section required to conform the seal adaptor to the non-uniform shape of a joint housing so configured to reduce weight and to save on material expense.
Known seal adaptors do not compensate for such variations in cross section.
According to the present invention, there is provided a seal adaptor assembly which is more uniform in stiffness and therefore will result in a more uniform compression of the seal adaptor which will provide a more uniform sealing/clamping force between the seal adaptor assembly and the boot seal and between the seal adaptor and the housing. The seal adaptor assembly is configured for use in a stroking universal joint of the type having drive channels and an outer drive-housing member having an exterior wall of non-uniform dimension including open spaces between the parts of the housing member enclosing the drive channels. The seal adaptor assembly includes an annular body and plurality of inserts having greater rigidity than the material of the annular body and wherein the inserts are located in the annular body at sections thereof that are located within outer housing spaces between the housing segments for the ball bores. The inserts are supported within the seal adaptor assembly at thin wall sections thereof and thereby provide for a more uniform compression of a resilient seal member between the housing and a clamp for holding the resilient seal member in place on the seal adaptor assembly.
Accordingly, it is an object of the present invention to provide a reinforced seal adaptor assembly for providing nearly uniform compression between clamped seal boot and a universal joint housing member having an outer surface with a non-uniform configuration e.g., a non-circular outer profile.
It is another object of the present invention to provide such a seal adaptor assembly between a seal and a clamp ring for securing the seal on a universal joint housing having an outer surface configured to reduce joint assembly weight and wherein sections of the adaptor assembly that fill outer open spaces in the joint housing member are reinforced.
It is another object of the present invention to provide such reinforcement by providing pockets in the seal adaptor assembly having spaced thin wall sections engageable respectively with the housing and with the seal and wherein a reinforcement member is supported within each of the pockets for providing a load transfer path from the seal to the housing member.
It is another object of the present invention to provide such a reinforcement as an insert plug made from stamped or formed sheet metal.
It is another object of the present invention to provide such an insert plug of powder metal material.
It is another object of the present invention to provide such an insert plug of rigid plastic material either hollow or solid.